The core of the Hulk, Dr. Robert Bruce Banner has been portrayed differently by different writers, but common themes persist. Banner, a genius, is emotionally withdrawn in most fashions. Banner designed the gamma bomb which caused his affliction, and the ironic twist of his self-inflicted fate has been one of the most persistent common themes. Arie Kaplan describes the character thus: Bruce Banner lives in a constant state of panic, always wary that the monster inside him will erupt, and therefore he cannot form meaningful bonds with anyone.”

Throughout the Hulk’s published history, writers have continued to frame Bruce Banner in these themes. Under different writers, his fractured personality led to transformations into different versions of the Hulk. These transformations are usually involuntary, and often writers have tied the transformation to emotional triggers, such as rage and fear. As the series has progressed, different writers have adapted the Hulk, changing Hulk’s personality to reflect changes in Banner’s physiology or psyche. Writers have also refined and changed some aspects of Banner’s personality, showing him as emotionally repressed, but capable of deep love for Betty Ross, and for solving problems posed to him. Under the writing of Paul Jenkins, Banner was shown to be a capable fugitive, applying deductive reasoning and observation to figure out the events transpiring around him. On the occasions that Banner has controlled the Hulk’s body, he has applied principles of physics to problems and challenges and used deductive reasoning. It was shown after his ability was taken away to turn in the Hulk by the Red Hulk that Banner has been extremely versatile as well as cunning when dealing with the many situations that followed.